Move waterfall FFT processing to it's own thread.

src/process/FFTVisualDataThread.cpp

@@ -0,0 +1,68 @@
+#include "FFTVisualDataThread.h"
+#include "CubicSDR.h"
+
+FFTVisualDataThread::FFTVisualDataThread() : linesPerSecond(DEFAULT_WATERFALL_LPS) {
+    lpsChanged.store(true);
+}
+
+FFTVisualDataThread::~FFTVisualDataThread() {
+    
+}
+
+void FFTVisualDataThread::setLinesPerSecond(int lps) {
+    linesPerSecond.store(lps);
+    lpsChanged.store(true);
+}
+
+int FFTVisualDataThread::getLinesPerSecond() {
+    return linesPerSecond.load();
+}
+
+SpectrumVisualProcessor *FFTVisualDataThread::getProcessor() {
+    return &wproc;
+}
+
+void FFTVisualDataThread::run() {
+    DemodulatorThreadInputQueue *pipeIQDataIn = (DemodulatorThreadInputQueue *)getInputQueue("IQDataInput");
+    SpectrumVisualDataQueue *pipeFFTDataOut = (SpectrumVisualDataQueue *)getOutputQueue("FFTDataOutput");
+    
+    fftDistrib.setInput(pipeIQDataIn);
+    fftDistrib.attachOutput(&fftQueue);
+    wproc.setInput(&fftQueue);
+    wproc.attachOutput(pipeFFTDataOut);
+    wproc.setup(2048);
+
+    std::cout << "FFT visual data thread started." << std::endl;
+    
+    while(!terminated) {
+        
+#ifndef _WIN32
+        usleep(15000);
+#else
+        Sleep(15);
+#endif
+        
+        int fftSize = wproc.getDesiredInputSize();
+        
+        if (fftSize) {
+            fftDistrib.setFFTSize(fftSize);
+        } else {
+            fftDistrib.setFFTSize(DEFAULT_FFT_SIZE);
+        }
+    
+        if (lpsChanged.load()) {
+            fftDistrib.setLinesPerSecond(linesPerSecond.load());
+            pipeIQDataIn->set_max_num_items(linesPerSecond.load());
+            lpsChanged.store(false);
+        }
+        
+        fftDistrib.run();
+        
+        while (!wproc.isInputEmpty()) {
+            wproc.run();
+        }
+    }
+    
+    std::cout << "FFT visual data thread terminated." << std::endl;
+}
+

src/process/FFTVisualDataThread.h

@@ -0,0 +1,24 @@
+#pragma once
+
+#include "IOThread.h"
+#include "SpectrumVisualProcessor.h"
+
+class FFTVisualDataThread : public IOThread {
+public:
+    FFTVisualDataThread();
+    ~FFTVisualDataThread();
+    
+    void setLinesPerSecond(int lps);
+    int getLinesPerSecond();
+    SpectrumVisualProcessor *getProcessor();
+    
+    void run();
+    
+protected:
+    FFTDataDistributor fftDistrib;
+    DemodulatorThreadInputQueue fftQueue;
+    SpectrumVisualProcessor wproc;
+    
+    std::atomic_int linesPerSecond;
+    std::atomic_bool lpsChanged;
+};

src/process/SpectrumVisualProcessor.h

@@ -111,7 +111,10 @@ protected:
             
             if (inp) {
                 if (inp->data.size() >= fftSize) {
-                    for (int i = 0, iMax = inp->data.size()-fftSize; i <= iMax; i += fftSize) {
+                    if (lineRateAccum + (lineRateStep * floor((double)inp->data.size()/(double)fftSize)) < 1.0) {
+                         // move along, nothing to see here..
+                        lineRateAccum += (lineRateStep * inp->data.size()/fftSize);
+                    } else for (int i = 0, iMax = inp->data.size()-fftSize; i <= iMax; i += fftSize) {
                         lineRateAccum += lineRateStep;
                         
                         if (lineRateAccum >= 1.0) {